Using a Cloud Witness for Clusters

On a client site recently a question was asked about the file share witness in a SQL Server failover cluster on-premises, and where to put it if you only have two sites. As always, it depends! Let’s look at some scenarios. Bear in mind that use of the Azure Cloud Witness requires Windows Server 2016 or later. Topology 1 Three node cluster with 2 nodes at primary and 1 at disaster recovery (DR) Most people want high availability at their “primary site” and are happy to have standalone capability at the business continuity (DR) site. To save storage costs, I would recommend a SQL Server failover clustered instance so you only have one set of storage at the primary site. On top of that you can place an availability group in asynchronous mode to a standalone server at your DR site. In this configuration there are several scenarios to consider, and they can all be served with a file share witness at the primary site, or use a cloud witness in azure. ...

Fri, 8 June 2018 · 7 min · Mark